One of Britain's biggest public transport operators, rail and bus company Arriva, is to be taken over by a German firm, in a £1.5bn deal. Aside from the irony of a franchise-owner on the UK's privatised railways being bought up by a state-owned foreign concern, Deutsche Bahn, news of the takeover has re-ignited the row over foreign ownership of key sectors of British industry.

With the controversy over Kraft's takeover of Cadbury, which resulted in Lord Mandelson calling for new rules on foreign acquisitions, only weeks past, Liberal Democrat shadow chancellor Vince Cable has criticised the lack of a public interest test for foreign takeovers of strategically important UK companies and utilities.

The counter-argument runs, though, that its openness to foreign capital and investment is one of the strengths of the British economy and that a more protectionist stance would damage prospects for growth and prosperity.

Presumably, Arriva's trains and buses will still run – possibly, more punctually even – so does it matter who owns them, any more than it matters who owns, say, a Premiership football team?